C-type lectin-like domain (CTLD) of the type found in the type 1 transmembrane proteins: P(platlet)-, E(endothelial)-, and L(leukocyte)- selectins (sels); CLECT_selectins_like: C-type lectin-like domain (CTLD) of the type found in the type 1 transmembrane proteins: P(platlet)-, E(endothelial)-, and L(leukocyte)- selectins (sels). CTLD refers to a domain homologous to the carbohydrate-recognition domains (CRDs) of the C-type lectins. P- E- and L-sels are cell adhesion receptors that mediate the initial attachment, tethering, and rolling of lymphocytes on inflamed vascular walls enabling subsequent lymphocyte adhesion and transmigration. L- sel is expressed constitutively on most leukocytes. P-sel is stored in the Weibel-Palade bodies of endothelial cells and in the alpha granules of platlets. E- sels are present on endothelial cells. Following platelet and/or endothelial cell activation P- sel is rapidly translocated to the cell surface and E-sel expression is induced. The initial step in leukocyte migration involves interactions of selectins with fucosylated, sialylated, and sulfated carbohydrate moieties on target ligands displayed on glycoprotein scaffolds on endothelial cells and leucocytes. A major ligand of P- E- and L-sels is PSGL-1 (P-sel glycoprotein ligand). Interactions of E- and P- sels with tumor cells may promote extravasation of cancer cells. Regulation of L-sel and P-sel function includes proteolytic shedding of the most extracellular portion (containing the CTLD) from the cell surface. Increased levels of the soluble form of P-sel in the plasma have been found in a number of diseases including coronary disease and diabetes. E- and P- sel also play roles in the development of synovial inflammation in inflammatory arthritis. Platelet P-sel, but not endothelial P-sel, plays a role in the inflammatory response and neointimal formation after arterial injury. Selectins may also function as signal-transducing receptors.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
1G1R_D        1 WTYHYSTKAYSWNISRKYCQNRYTDLVAIQNKNEIDYLN-KVLPYYSSYYWIGIRKNNKTWTWVGTKKALtNEAENWADN 79
Cdd:cd03592   1 WTYHYSTEKMTFNEAVKYCKSRGTDLVAIQNAEENALLNgFALKYNLGYYWIDGNDINNEGTWVDTDKKE-LEYKNWAPG 79

                        90       100       110       120
                ....*....|....*....|....*....|....*....|
1G1R_D       80 EPNNKRnNEDCVEIYIKspsAPGKWNDEHCLKKKHALCYT 119
Cdd:cd03592  80 EPNNGR-NENCLEIYIK---DNGKWNDEPCSKKKSAICYT 115

C-type lectin-like domain (CTLD) of the type found in the type 1 transmembrane proteins: P(platlet)-, E(endothelial)-, and L(leukocyte)- selectins (sels); CLECT_selectins_like: C-type lectin-like domain (CTLD) of the type found in the type 1 transmembrane proteins: P(platlet)-, E(endothelial)-, and L(leukocyte)- selectins (sels). CTLD refers to a domain homologous to the carbohydrate-recognition domains (CRDs) of the C-type lectins. P- E- and L-sels are cell adhesion receptors that mediate the initial attachment, tethering, and rolling of lymphocytes on inflamed vascular walls enabling subsequent lymphocyte adhesion and transmigration. L- sel is expressed constitutively on most leukocytes. P-sel is stored in the Weibel-Palade bodies of endothelial cells and in the alpha granules of platlets. E- sels are present on endothelial cells. Following platelet and/or endothelial cell activation P- sel is rapidly translocated to the cell surface and E-sel expression is induced. The initial step in leukocyte migration involves interactions of selectins with fucosylated, sialylated, and sulfated carbohydrate moieties on target ligands displayed on glycoprotein scaffolds on endothelial cells and leucocytes. A major ligand of P- E- and L-sels is PSGL-1 (P-sel glycoprotein ligand). Interactions of E- and P- sels with tumor cells may promote extravasation of cancer cells. Regulation of L-sel and P-sel function includes proteolytic shedding of the most extracellular portion (containing the CTLD) from the cell surface. Increased levels of the soluble form of P-sel in the plasma have been found in a number of diseases including coronary disease and diabetes. E- and P- sel also play roles in the development of synovial inflammation in inflammatory arthritis. Platelet P-sel, but not endothelial P-sel, plays a role in the inflammatory response and neointimal formation after arterial injury. Selectins may also function as signal-transducing receptors.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
1G1R_D        1 WTYHYSTKAYSWNISRKYCQNRYTDLVAIQNKNEIDYLN-KVLPYYSSYYWIGIRKNNKTWTWVGTKKALtNEAENWADN 79
Cdd:cd03592   1 WTYHYSTEKMTFNEAVKYCKSRGTDLVAIQNAEENALLNgFALKYNLGYYWIDGNDINNEGTWVDTDKKE-LEYKNWAPG 79

                        90       100       110       120
                ....*....|....*....|....*....|....*....|
1G1R_D       80 EPNNKRnNEDCVEIYIKspsAPGKWNDEHCLKKKHALCYT 119
Cdd:cd03592  80 EPNNGR-NENCLEIYIK---DNGKWNDEPCSKKKSAICYT 115

C-type lectin (CTL) or carbohydrate-recognition domain (CRD); Many of these domains function as calcium-dependent carbohydrate binding modules.

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
1G1R_D           1 WTYHYSTKAYSWNISRKYCQNRYTDLVAIQNKNEIDYLNKVLPYY--SSYYWIGIR--KNNKTWTWVGTKKALTNeaENW 76
Cdd:smart00034  11 KCYKFSTEKKTWEDAQAFCQSLGGHLASIHSEAENDFVASLLKNSgsSDYYWIGLSdpDSNGSWQWSDGSGPVSY--SNW 88

                           90       100       110       120
                   ....*....|....*....|....*....|....*....|.
1G1R_D          77 ADNEPNNkrNNEDCVEIYIKSpsapGKWNDEHCLKKKHALC 117
Cdd:smart00034  89 APGEPNN--SSGDCVVLSTSG----GKWNDVSCTSKLPFVC 123

EGF-like domain; There is no clear separation between noise and signal. pfam00053 is very similar, but has 8 instead of 6 conserved cysteines. Includes some cytokine receptors. The EGF domain misses the N-terminus regions of the Ca2+ binding EGF domains (this is the main reason of discrepancy between swiss-prot domain start/end and Pfam). The family is hard to model due to many similar but different sub-types of EGF domains. Pfam certainly misses a number of EGF domains.

                          10        20        30
                  ....*....|....*....|....*....|
1G1R_D        122 CQDMSCSKQGECLETIGNYTCSCYPGFYGP 151
Cdd:pfam00008   1 CAPNPCSNGGTCVDTPGGYTCICPEGYTGK 30

C-type lectin-like domain (CTLD) of the type found in the type 1 transmembrane proteins: P(platlet)-, E(endothelial)-, and L(leukocyte)- selectins (sels); CLECT_selectins_like: C-type lectin-like domain (CTLD) of the type found in the type 1 transmembrane proteins: P(platlet)-, E(endothelial)-, and L(leukocyte)- selectins (sels). CTLD refers to a domain homologous to the carbohydrate-recognition domains (CRDs) of the C-type lectins. P- E- and L-sels are cell adhesion receptors that mediate the initial attachment, tethering, and rolling of lymphocytes on inflamed vascular walls enabling subsequent lymphocyte adhesion and transmigration. L- sel is expressed constitutively on most leukocytes. P-sel is stored in the Weibel-Palade bodies of endothelial cells and in the alpha granules of platlets. E- sels are present on endothelial cells. Following platelet and/or endothelial cell activation P- sel is rapidly translocated to the cell surface and E-sel expression is induced. The initial step in leukocyte migration involves interactions of selectins with fucosylated, sialylated, and sulfated carbohydrate moieties on target ligands displayed on glycoprotein scaffolds on endothelial cells and leucocytes. A major ligand of P- E- and L-sels is PSGL-1 (P-sel glycoprotein ligand). Interactions of E- and P- sels with tumor cells may promote extravasation of cancer cells. Regulation of L-sel and P-sel function includes proteolytic shedding of the most extracellular portion (containing the CTLD) from the cell surface. Increased levels of the soluble form of P-sel in the plasma have been found in a number of diseases including coronary disease and diabetes. E- and P- sel also play roles in the development of synovial inflammation in inflammatory arthritis. Platelet P-sel, but not endothelial P-sel, plays a role in the inflammatory response and neointimal formation after arterial injury. Selectins may also function as signal-transducing receptors.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
1G1R_D        1 WTYHYSTKAYSWNISRKYCQNRYTDLVAIQNKNEIDYLN-KVLPYYSSYYWIGIRKNNKTWTWVGTKKALtNEAENWADN 79
Cdd:cd03592   1 WTYHYSTEKMTFNEAVKYCKSRGTDLVAIQNAEENALLNgFALKYNLGYYWIDGNDINNEGTWVDTDKKE-LEYKNWAPG 79

                        90       100       110       120
                ....*....|....*....|....*....|....*....|
1G1R_D       80 EPNNKRnNEDCVEIYIKspsAPGKWNDEHCLKKKHALCYT 119
Cdd:cd03592  80 EPNNGR-NENCLEIYIK---DNGKWNDEPCSKKKSAICYT 115

C-type lectin (CTL)/C-type lectin-like (CTLD) domain; CLECT: C-type lectin (CTL)/C-type lectin-like (CTLD) domain; protein domains homologous to the carbohydrate-recognition domains (CRDs) of the C-type lectins. This group is chiefly comprised of eukaryotic CTLDs, but contains some, as yet functionally uncharacterized, bacterial CTLDs. Many CTLDs are calcium-dependent carbohydrate binding modules; other CTLDs bind protein ligands, lipids, and inorganic surfaces, including CaCO3 and ice. Animal C-type lectins are involved in such functions as extracellular matrix organization, endocytosis, complement activation, pathogen recognition, and cell-cell interactions. For example: mannose-binding lectin and lung surfactant proteins A and D bind carbohydrates on surfaces (e.g. pathogens, allergens, necrotic, and apoptotic cells) and mediate functions associated with killing and phagocytosis; P (platlet)-, E (endothelial)-, and L (leukocyte)- selectins (sels) mediate the initial attachment, tethering, and rolling of lymphocytes on inflamed vascular walls enabling subsequent lymphocyte adhesion and transmigration. CTLDs may bind a variety of carbohydrate ligands including mannose, N-acetylglucosamine, galactose, N-acetylgalactosamine, and fucose. Several CTLDs bind to protein ligands, and only some of these binding interactions are Ca2+-dependent; including the CTLDs of Coagulation Factors IX/X (IX/X) and Von Willebrand Factor (VWF) binding proteins, and natural killer cell receptors. C-type lectins, such as lithostathine, and some type II antifreeze glycoproteins function in a Ca2+-independent manner to bind inorganic surfaces. Many proteins in this group contain a single CTLD; these CTLDs associate with each other through several different surfaces to form dimers, trimers, or tetramers, from which ligand-binding sites project in different orientations. Various vertebrate type 1 transmembrane proteins including macrophage mannose receptor, endo180, phospholipase A2 receptor, and dendritic and epithelial cell receptor (DEC205) have extracellular domains containing 8 or more CTLDs; these CTLDs remain in the parent model. In some members (IX/X and VWF binding proteins), a loop extends to the adjoining domain to form a loop-swapped dimer. A similar conformation is seen in the macrophage mannose receptor CRD4's putative non-sugar bound form of the domain in the acid environment of the endosome. Lineage specific expansions of CTLDs have occurred in several animal lineages including Drosophila melanogaster and Caenorhabditis elegans; these CTLDs also remain in the parent model.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
1G1R_D        1 WTYHYSTKAYSWNISRKYCQNRYTDLVAIQNKNEIDYL-NKVLPYYSSYYWIGIRKN--NKTWTWVGTKKALTNeaENWA 77
Cdd:cd00037   1 SCYKFSTEKLTWEEAQEYCRSLGGHLASIHSEEENDFLaSLLKKSSSSDVWIGLNDLssEGTWKWSDGSPLVDY--TNWA 78

                        90       100       110       120
                ....*....|....*....|....*....|....*....|.
1G1R_D       78 DNEPNNKrNNEDCVEIYIkspSAPGKWNDEHCLKKKHALCY 118
Cdd:cd00037  79 PGEPNPG-GSEDCVVLSS---SSDGKWNDVSCSSKLPFICE 115

C-type lectin-like domain (CTLD) of the type found in human dendritic cell (DC)-specific intercellular adhesion molecule 3-grabbing non-integrin (DC-SIGN) and the related receptor, DC-SIGN receptor (DC-SIGNR); CLECT_DC-SIGN_like: C-type lectin-like domain (CTLD) of the type found in human dendritic cell (DC)-specific intercellular adhesion molecule 3-grabbing non-integrin (DC-SIGN) and the related receptor, DC-SIGN receptor (DC-SIGNR). This group also contains proteins similar to hepatic asialoglycoprotein receptor (ASGP-R) and langerin in human. These proteins are type II membrane proteins with a CTLD ectodomain. CTLD refers to a domain homologous to the carbohydrate-recognition domains (CRDs) of the C-type lectins. DC-SIGN is thought to mediate the initial contact between dendritic cells and resting T cells, and may also mediate the rolling of DCs on epithelium. DC-SIGN and DC-SIGNR bind to oligosaccharides present on human tissues, as well as, on pathogens including parasites, bacteria, and viruses. DC-SIGN and DC-SIGNR bind to HIV enhancing viral infection of T cells. DC-SIGN and DC-SIGNR are homotetrameric, and contain four CTLDs stabilized by a coiled coil of alpha helices. The hepatic ASGP-R is an endocytic recycling receptor which binds and internalizes desialylated glycoproteins having a terminal galactose or N-acetylgalactosamine residues on their N-linked carbohydrate chains, via the clathrin-coated pit mediated endocytic pathway, and delivers them to lysosomes for degradation. It has been proposed that glycoproteins bearing terminal Sia (sialic acid) alpha2, 6GalNAc and Sia alpha2, 6Gal are endogenous ligands for ASGP-R and that ASGP-R participates in regulating the relative concentration of serum glycoproteins bearing alpha 2,6-linked Sia. The human ASGP-R is a hetero-oligomer composed of two subunits, both of which are found within this group. Langerin is expressed in a subset of dendritic leukocytes, the Langerhans cells (LC). Langerin induces the formation of Birbeck Granules (BGs) and associates with these BGs following internalization. Langerin binds, in a calcium-dependent manner, to glyco-conjugates containing mannose and related sugars mediating their uptake and degradation. Langerin molecules oligomerize as trimers with three CTLDs held together by a coiled-coil of alpha helices.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
1G1R_D        3 YHYSTKAYSWNISRKYCQNRYTDLVAIQNKNEIDYLNKVLPyYSSYYWIGIRKNNK--TWTWV-GTKkaLTNEAENWADN 79
Cdd:cd03590  13 YFFSTEKKSWEESRQFCEDMGAHLVIINSQEEQEFISKILS-GNRSYWIGLSDEETegEWKWVdGTP--LNSSKTFWHPG 89

                        90       100       110
                ....*....|....*....|....*....|....*....
1G1R_D       80 EPNNKR-NNEDCVEIYikspSAPGKWNDEHCLKKKHALC 117
Cdd:cd03590  90 EPNNWGgGGEDCAELV----YDSGGWNDVPCNLEYRWIC 124

C-type lectin-like domain (CTLD) of the type found in human collectins including lung surfactant proteins A and D, mannose- or mannan binding lectin (MBL), and CL-L1 (collectin liver 1); CLECT_collectin_like: C-type lectin-like domain (CTLD) of the type found in human collectins including lung surfactant proteins A and D, mannose- or mannan binding lectin (MBL), and CL-L1 (collectin liver 1). CTLD refers to a domain homologous to the carbohydrate-recognition domains (CRDs) of the C-type lectins. The CTLDs of these collectins bind carbohydrates on surfaces (e.g. pathogens, allergens, necrotic, or apoptotic cells) and mediate functions associated with killing and phagocytosis. MBPs recognize high mannose oligosaccharides in a calcium dependent manner, bind to a broad range of pathogens, and trigger cell killing by activating the complement pathway. MBP also acts directly as an opsonin. SP-A and SP-D in addition to functioning as host defense components, are components of pulmonary surfactant which play a role in surfactant homeostasis. Pulmonary surfactant is a phospholipid-protein complex which reduces the surface tension within the lungs. SP-A binds the major surfactant lipid: dipalmitoylphosphatidylcholine (DPPC). SP-D binds two minor components of surfactant that contain sugar moieties: glucosylceramide and phosphatidylinositol (PI). MBP and SP-A, -D monomers are homotrimers with an N-terminal collagen region and three CTLDs. Multiple homotrimeric units associate to form supramolecular complexes. MBL deficiency results in an increased susceptibility to a large number of different infections and to inflammatory disease, such as rheumatoid arthritis.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
1G1R_D        3 YHYSTKA-YSWNISRKYCQNRYTDLVAIQNKNEIDYLNKVLPYYSSYYWIGI--RKNNKTWTWVgTKKALTneAENWADN 79
Cdd:cd03591   3 IFVTNGEeKNFDDAQKLCSEAGGTLAMPRNAAENAAIASYVKKGNTYAFIGItdLETEGQFVYL-DGGPLT--YTNWKPG 79

                        90       100       110
                ....*....|....*....|....*....|....*...
1G1R_D       80 EPNNKRNNEDCVEIYikspsAPGKWNDEHCLKKKHALC 117
Cdd:cd03591  80 EPNNAGGGEDCVEMY-----TSGKWNDVACNLTRLFVC 112

C-type lectin-like domain (CTLD) of the type found in lectins TC14, TC14-2, TC14-3, and TC14-4 from the budding tunicate Polyandrocarpa misakiensis and PfG6 from the Acorn worm; CLECT_TC14_like: C-type lectin-like domain (CTLD) of the type found in lectins TC14, TC14-2, TC14-3, and TC14-4 from the budding tunicate Polyandrocarpa misakiensis and PfG6 from the Acorn worm. CTLD refers to a domain homologous to the carbohydrate-recognition domains (CRDs) of the C-type lectins. TC14 is homodimeric. The CTLD of TC14 binds D-galactose and D-fucose. TC14 is expressed constitutively by multipotent epithelial and mesenchymal cells and plays in role during budding, in inducing the aggregation of undifferentiated mesenchymal cells to give rise to epithelial forming tissue. TC14-2 and TC14-3 shows calcium-dependent galactose binding activity. TC14-3 is a cytostatic factor which blocks cell growth and dedifferentiation of the atrial epithelium during asexual reproduction. It may also act as a differentiation inducing factor. Galactose inhibits the cytostatic activity of TC14-3. The gene for Acorn worm PfG6 is gill-specific; PfG6 may be a secreted protein.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
1G1R_D       17 KYCQNRYTDLVAIQNKnEIDYLNKVLPYYSSY---YWIGI---RKNNKTWTWvGTKKALTNEAENWADNEPNNKRNNEDC 90
Cdd:cd03601  17 AFCRSRGMRLASLAMR-DSEMRDAILAFTLVKghgYWVGAdnlQDGEYDFLW-NDGVSLPTDSDLWAPNEPSNPQSRQLC 94

                        90       100
                ....*....|....*....|....*..
1G1R_D       91 VEIYIKspsaPGKWNDEHCLKKKHALC 117
Cdd:cd03601  95 VQLWSK----YNLLDDEYCGRAKRVIC 117

C-type lectin-like domain (CTLD) of the type found in CEL-1 from Cucumaria echinata and Echinoidin from Anthocidaris crassispina; CLECT_CEL-1_like: C-type lectin-like domain (CTLD) of the type found in CEL-1 from Cucumaria echinata and Echinoidin from Anthocidaris crassispina. CTLD refers to a domain homologous to the carbohydrate-recognition domains (CRDs) of the C-type lectins. The CEL-1 CTLD binds three calcium ions and has a high specificity for N-acteylgalactosamine (GalNAc). CEL-1 exhibits strong cytotoxicity which is inhibited by GalNAc. This protein may play a role as a toxin defending against predation. Echinoidin is found in the coelomic fluid of the sea urchin and is specific for GalBeta1-3GalNAc. Echinoidin has a cell adhesive activity towards human cancer cells which is not mediated through the CTLD. Both CEL-1 and Echinoidin are multimeric proteins comprised of multiple dimers linked by disulfide bonds.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
1G1R_D       11 SWNISRKYCQN-----RYTDLVAIQNKNEIDYlnkVLPYYSSYY--------WIGI--RKNNKTWTWV-GTkkalTNEAE 74
Cdd:cd03589  21 TWEEAELRCRSfsipgLIAHLVSIHSQEENDF---VYDLFESSRgpdtpyglWIGLhdRTSEGPFEWTdGS----PVDFT 93

                        90       100       110       120
                ....*....|....*....|....*....|....*....|...
1G1R_D       75 NWADNEPNNKRNNEDCVEIYiKSPSAPGKWNDEHCLKKKHALC 117
Cdd:cd03589  94 KWAGGQPDNYGGNEDCVQMW-RRGDAGQSWNDMPCDAVFPYIC 135

C-type lectin-like domain (CTLD) of the type found in Human REG-1 (lithostathine), REG-4, and avian eggshell-specific proteins: ansocalcin, structhiocalcin-1(SCA-1), and -2(SCA-2); CLECT_REG-1_like: C-type lectin-like domain (CTLD) of the type found in Human REG-1 (lithostathine), REG-4, and avian eggshell-specific proteins: ansocalcin, structhiocalcin-1(SCA-1), and -2(SCA-2). CTLD refers to a domain homologous to the carbohydrate-recognition domains (CRDs) of the C-type lectins. REG-1 is a proliferating factor which participates in various kinds of tissue regeneration including pancreatic beta-cell regeneration, regeneration of intestinal mucosa, regeneration of motor neurons, and perhaps in tissue regeneration of damaged heart. REG-1 may play a role on the pathophysiology of Alzheimer's disease and in the development of gastric cancers. Its expression is correlated with reduced survival from early-stage colorectal cancer. REG-1 also binds and aggregates several bacterial strains from the intestinal flora and it has been suggested that it is involved in the control of the intestinal bacterial ecosystem. Rat lithostathine has calcium carbonate crystal inhibitor activity in vitro. REG-IV is unregulated in pancreatic, gastric, hepatocellular, and prostrate adenocarcinomas. REG-IV activates the EGF receptor/Akt/AP-1 signaling pathway in colorectal carcinoma. Ansocalcin, SCA-1 and -2 are found at high concentration in the calcified egg shell layer of goose and ostrich, respectively and tend to form aggregates. Ansocalcin nucleates calcite crystal aggregates in vitro.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
1G1R_D        3 YHYSTKAYSWNISRKYCQNRY--TDLVAIQNKNEIDYLNKVLPYY---SSYYWIGIRKNNKTWTWVGTKKALTNEAeNWA 77
Cdd:cd03594  13 YGYFRQPLSWSDAELFCQKYGpgAHLASIHSPAEAAAIASLISSYqkaYQPVWIGLHDPQQSRGWEWSDGSKLDYR-SWD 91

                        90       100       110       120
                ....*....|....*....|....*....|....*....|
1G1R_D       78 DNEPnnKRNNEDCVEiyIKSPSAPGKWNDEHCLKKKHALC 117
Cdd:cd03594  92 RNPP--YARGGYCAE--LSRSTGFLKWNDANCEERNPFIC 127

Epidermal growth factor domain, found in epidermal growth factor (EGF) presents in a large number of proteins, mostly animal; the list of proteins currently known to contain one or more copies of an EGF-like pattern is large and varied; the functional significance of EGF-like domains in what appear to be unrelated proteins is not yet clear; a common feature is that these repeats are found in the extracellular domain of membrane-bound proteins or in proteins known to be secreted (exception: prostaglandin G/H synthase); the domain includes six cysteine residues which have been shown to be involved in disulfide bonds; the main structure is a two-stranded beta-sheet followed by a loop to a C-terminal short two-stranded sheet; Subdomains between the conserved cysteines vary in length; the region between the 5th and 6th cysteine contains two conserved glycines of which at least one is present in most EGF-like domains; a subset of these bind calcium.

                        10        20
                ....*....|....*....|....*....
1G1R_D      127 CSKQGECLETIGNYTCSCYPGFYGPE-CE 154
Cdd:cd00053   8 CSNGGTCVNTPGSYRCVCPPGYTGDRsCE 36